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    <title>Document</title>
    <script>
        var r = 5;
        const PI = 3.14;
        var l = 2 * r * PI;
       
        var s = PI * r * r;
        console.log("圆的周长为",l.toFixed(2));
        console.log("圆的面积为",s)
    </script>
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